Science
Class 06
chapter 7
Getting to know plants
Plant contain different parts like stem root flower fruit leaves
** Plants are usually grouped into herbs, shrubs, trees and climbers based on their height stem and branches.
Herbs :- Plants with green and candle stems are called herbs. They are usually short and may not have many branches.
These are smaller than our size.
Ex. Wheat, sunflower, rice, maize etc
Shurbs :- Some plants develop branches near the base of stem. The stem is hard but not very thick. Such plant are called shurbs.
These are about similar our size.
Ex. Lemon, China rose, Jasmine, nerium etc.
Trees :- Some plants are very tall and have hard and thick stem. Next time have branches in the upper part much above the ground. Such plants are called trees. Which live many years.
Ex. Mango, neem, banyan, coconut etc.
Creepers :- Plants with weak stems that cannot stand upright but spread on the ground are called creepers.
Ex. Pumpkin, watermelon etc.
Climbers :- Plants have weak stems and cannot stand erect. That take support of their trees and climb on them.
Ex. Grapes, pea, vine etc.
Creepers and climbers are different from herb, shurb and tree.
Stem :- It gives rise to a number of branch that we are leaves. The stem bear leaves, flowers and fruits.
Stem helps in upward movement of water. The water and mineral go to leaves and other plant parts attached to stem.
Leaf :- Leaf arises from the leaf base. A leaf usually has a petiole and a lamina.
Parts of leaf
(1) Petiole :- The part of leaf by which it is attached to the stem is called petiole.
(2) Lamina :- The broad green part of the leaf is called lamina.
(3) Vein :- These are the network of small, narrow, tubelight structure on both sides of the middle present in the middle of leaf.
(4) Mid rib :- a prominent line in the middle of a leaf. This is called the mid rib.
Leaf venation :- The design made by veins in a leaf is called the leaf venation.
(1) Reticulate :- Net like design on both sides of midrib of the leaf, the venation is reticulate.
Ex. Tulsi, papaya, peepal etc.
(2) Parallel venation :- In a plant the veins of the leaf blade or lamina exhibiting The parallel pattern from the base to the tip is known as parallel venation.
Ex. Grass, maize etc.
Transpiration :- water comes out of leaves in the form of vapour by the process called transpiration.
Plants release a lot of water into air through this process.
Transpiration occur with the help of tiny pore called stomata, which present lower part of the leaf.
Photosynthesis :- Leaves prepare their food in the presence of sunlight and green coloured substance (chlorophyll) present in them. For this, they also use water and carbon dioxide, this process is called photosynthesis.
Oxygen is given out in this process.
** The food prepared by leaves ultimately gets stored in different part of plants.
** The stem supplies leaf with water.
** The leaf uses the water to make food.
** The leaves also lose water through transpiration.
Root :- It is the underground portion of the plant. Two types of roots are
(1) Tap root :- it is the main primary root arises from lower end of the stem. A number of tiny branches called secondary roots or lateral roots.
Ex. Mustard, neem, rose etc
(2) Fibrous root :- a bunch of root arises from the bae of stem and all roots seem similar and these are called fibrous root.
Ex. Wheat,maize,rice,paddy etc.
** Roots absorb water and nutrients from the soil.
** Roots help the plant to stand erect.
** Roots check soil erosion and store food. Which is prepared by leaf.
Flower :- it is reproductive parts of flowering plant.
Parts of flower:-
(1) petals
(2) sepals
(3) stamen -
(a) Anther (b)filament
(4) pistil -
(a) stigma (b) style (c) ovary
(1) Petals :- Brightly coloured leaf like structure present inside the sepals. Petals attract the insects and help in the process of reproduction.
Different flower have petals of different colours. It is most prominent part of bud
(2) Sepals :- Small green leaf like structure on the thalamus. They protect the flower
(3) Stamen :- These are long, thin and needle like structure. These are male organ of the flower. It consist two parts which are
(a) Anther :- The swallon tip of each stamen that encloses in it a small powdery substance called pollen grains.
(b) Filament :- Long stall like structure that join the answer with thalamus.
(4) Pistil - It is female organ of the flower. Which is flask shaped organ in the centre of flower. It consist three parts which are
(a) Stigma :- Small, round and sticky part of the pistil at the top of the style that traps the pollen grains.
(b) Style :- Long, thin tube light structure which is swollen at the base.
(c) Ovary :- Lower swollen part of pistil that contains ovules.
Ovule :- When cut the ovary in different parts (transverse cut and longitudinal cut) we see some small bead like structure inside the ovary. They are called a ovule.
** Flower help in reproduction.
** Flower become fruits that store food and seeds.
Petiole :- It is the stalk that attaches the leaf blade of the stem.
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